The children were assessed on their reading and maths abilities, physical health and their social-emotional adjustment.

Results showed that family type is not the overriding influence on a child's well-being.

Instead, the evidence shows it is more important that the child has well-educated parents - particularly in the case of their mother - than parents who stay together.

"Once we control for parents’ education and household living standards, our findings show only a slight or, in many cases, a complete absence of differences in the indicators of child well-being between children of two-parent married families, co-habiting families, step-families, and one-parent families," said Professor Tony Fahey, the lead author of the study.

"All other things being equal, this research reveals that it is more important for children’s well-being that they have well-educated parents (particularly in the case of the mother) than that they have parents who stay together."

Seventy-nine percent of the children studied lived with both their natural parents, 17.5% with lone parents, and 3% with step-families.

The study finds that stable married families are more likely to have more children. Married couples were shown to have three children on average, while unmarried lone parents were shown to have 1.8 children on average.

The report also found better-educated women were less likely to have children early in life, while the least-educated mothers were more likely to have children before the age of 25.

The report is being launched today by Children's Minister Frances Fitzgerald.